There have been many different types and kinds of small economical land vehicles. For example, reference may be made to U.S. Pat. No. 4,133,402 of applicant, and the prior art references cited therein. In the foregoing mentioned patent, outrigger side wheels are mounted on a conventional motorcycle to provide a relatively low-cost fuel-efficient vehicle. In this regard, motorcycles are fuel-efficient vehicles, but they are not very practical for every day use to meet transportation needs. Thus, the automobile is far more practical for every day transportation needs, due to its closed-body construction for protecting the passengers therein. Also, the automobile is far more safe and stable in its operation as compared to motorcycles. Thus, in order to be more fuel-efficient and to minimize the manufacturing cost, automobiles have been made more compact in size and weight.
However, while being somewhat more fuel-efficient as compared to heavier vehicles, smaller size automobiles have not been entirely satisfactory for some applications in that they have not been as safe and as fuel efficient as might be desired. The smaller, light-weight vehicles are less maneuverable, especially when moving into a turn. The bodies of such vehicles have been ordinarily boxlike in configuration, and hence they have not been very streamlined in their outer contour to aid in reducing wind resistance aerodynamically, thereby limiting greatly their fuel efficiency. Thus, it would be highly desirable to have a small light-weight land vehicle, which is relatively stable and highly maneuverable, especially in its turning operations, and which is aerodynamically designed for aiding fuel efficiency.
As shown in U.S. Pat. No. 3,236,323, a triple track land vehicle having four wheels arranged in a diamond-shaped configuration, has been proposed since it can be readily provided with a vehicle body having a relatively smooth aerodynamic outer contour, to improve fuel economy. Also, such a vehicle could be provided with a single drive wheel, thereby eliminating the need for a differential. A differential is expensive to manufacture and to assemble to the vehicle, and adds unwanted weight to the vehicle and power-robbing friction to the drive train.
While such a four-wheel vehicle may be less expensive to manufacture and fuel-efficient to operate, the single drive wheel should remain in frictional engagement with the ground for more efficient operation. The problem is especially acute where the terrain is very uneven and where the drive wheel may tend to bounce. Thus, such a triple track vehicle should have provisions for maintaining the drive wheel in engagement with the ground. Also, such a vehicle should be safe to operate and be highly maneuverable, especially in turns. Such a vehicle should be relatively inexpensive to manufacture and have a light weight fuel-efficient design.